Gas pipe lines have been transmitting compressible substances at increasingly higher pressures over the past several years. Notable improvements in the integrity and strength of pipes which carry the compressed gas are the single most important factor in allowing gas to be transported at ever increasing pressures.
Consequently, as the ability of pipes to carry greater through-put increases, there also arises a need to provide more sophisticated testing equipment to assure that the quality of the pipes is maintained at these elevated pressures. Traditionally, pipe coupons have been first cut from production-line pipes and then tested with a pendulum-type drop weight tear test machine. The pendulum is dependent upon a specific mass falling by gravity through a known distance to attain a calculated velocity as it reaches its lowest point where its energy is greatest.
The following documents reflect the state of the art of which applicants are aware and are included herewith to discharge applicants' acknowledged duty to disclose relevant prior art. It is stipulated, however, that none of these documents teach singly nor render obvious when considered in any conceivable combination the nexus of the instant invention as hereinafter claimed.
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